I'm trying to unmount a guest cdrom using libvirt_domain_update_device (via php-libvirt). The guest cdrom is currently mounted via Ceph, via this XML: <disk type='network' device='cdrom'> <driver name='qemu' type='raw'/> <auth username='cdroms'> <secret type='ceph' uuid='XXXX'/> </auth> <source protocol='rbd' name='cdrom/test'/> <target dev='hdc' bus='ide'/> <readonly/> <address type='drive' controller='0' bus='1' target='0' unit='0'/> </disk> In order to unmount it, I'm trying to use this XML: <disk type='file' device='cdrom'> <driver name='qemu' type='raw'/> <target dev='hdc' bus='ide'/> <readonly/> <alias name='ide0-1-0'/> <address type='drive' controller='0' bus='1' target='0' unit='0'/> </disk> However, I'm getting an error from libvirt: 'internal error: invalid secret type 'ceph''. I suspect this is because it's still trying to use the authentication information from the old cdrom definition. How do I convince it to not do this? I've tried specifiying an empty <auth/> block, but that generates it's own error ('missing username for auth')